Plasma D-dimer concentrations predicting stroke risk and rivaroxaban benefit in patients with heart failure and sinus rhythm: an analysis from the COMMANDER-HF trial

High Risk of Stroke in Patients With Worsening Heart Failure, Reduced Ejection Fraction, Coronary Heart Disease and Sinus Rhythm: Risk Prediction Score Analysis From the COMMANDER-HF Trial

BACKGROUND

Patients with heart failure with reduced ejection fraction (HFrEF) and sinus rhythm have a heightened risk of stroke. Whether anticoagulation benefits these patients is uncertain. In this post hoc analysis of the A Study to Assess the Effectiveness and Safety of Rivaroxaban in Reducing the Risk of Death, Myocardial Infarction, or Stroke in Participants with Heart Failure and Coronary Artery Disease Following an Episode of Decompensated Heart Failure (COMMANDER-HF) trial we evaluated how a previously validated risk model consisting of 3 variables (history of prior stroke, insulin-treated diabetes, and N-terminal pro-B-type natriuretic peptide level) would perform, compared with plasma d-dimer, for stroke prediction and estimation of the benefit of low-dose rivaroxaban.

METHODS AND RESULTS

Stroke risk and treatment effect were computed across risk score and plasma d-dimer tertiles. Risk score was available in 58% of the COMMANDER-HF population (n = 2928). Over a median follow-up of 512 days (range 342-747 days), 60 patients experienced a stroke (14.6 per 1000 patient-years). The risk model did not identify patients at higher risk of stroke and showed a low overall prognostic performance (C-index = 0.53). The effect of rivaroxaban on stroke was homogeneous across risk score tertiles (P-interaction = .67). Among patients in whom the risk score was estimated, d-dimer was available in 2343 (80%). d-dimer had an acceptable discrimination performance for stroke prediction (C-index = 0.66) and higher plasma d-dimer concentrations were associated with higher rates of stroke (ie, tertile 3 vs tertile 1, hazard ratio 3.65, 95% confidence interval 1.59-8.39, P = .002). Treatment with low-dose rivaroxaban reduced the incidence of stroke in patients at highest risk by d-dimer levels (ie, >515 ng/mL, hazard ratio 0.42, 95% confidence interval 0.18-0.95, P-interaction = .074), without any safety concerns.

CONCLUSIONS

In our analysis, plasma d-dimer concentrations performed better than a previously described 3-variable risk score for stroke prediction in patients with heart failure with reduced ejection fraction, a recent clinical worsening and sinus rhythm as enrolled in the COMMANDER-HF trial. In these patients, a raised plasma d-dimer concentration identified patients who might benefit most from rivaroxaban.

The effect of rivaroxaban on biomarkers in blood and plasma: a review of preclinical and clinical evidence

Rivaroxaban is a direct, oral factor Xa inhibitor that is used for the prevention and treatment of various thromboembolic disorders. Several preclinical and clinical studies have utilized specific molecules as biomarkers to investigate the potential role of rivaroxaban beyond its anticoagulant activity and across a range of biological processes. The aim of this review is to summarize the existing evidence regarding the use of blood-based biomarkers to characterize the effects of rivaroxaban on coagulation and other pathways, including platelet activation, inflammation and endothelial effects. After a literature search using PubMed, almost 100 preclinical and clinical studies were identified that investigated the effects of rivaroxaban using molecular biomarkers. In agreement with the preclinical data, clinical studies reported a trend for reduction in the blood concentrations of D-dimers, thrombin-antithrombin complex and prothrombin fragment 1 + 2 following treatment with rivaroxaban in both healthy individuals and those with various chronic conditions. Preclinical and also some clinical studies have also reported a potential impact of rivaroxaban on the concentrations of platelet activation biomarkers (von Willebrand factor, P-selectin and thrombomodulin), endothelial activation biomarkers (matrix metalloproteinase-9, intercellular adhesion molecule-1 and vascular cell adhesion molecule-1) and inflammation biomarkers (interleukin-6, tumor necrosis factor-α and monocyte chemoattractant protein-1). Based on the results of biomarker studies, molecular biomarkers can be used in addition to traditional coagulation assays to increase the understanding of the anticoagulation effects of rivaroxaban. Moreover, there is preliminary evidence to suggest that rivaroxaban may have an impact on the biological pathways of platelet activation, endothelial activation and inflammation; however, owing to paucity of clinical data to investigate the trends reported in preclinical studies, further investigation is required to clarify these observations.

D-dimer and outcomes in hospitalized heart failure patients across the ejection fraction phenotypes

AIMS

The prognostic significance of D-dimer in hospitalized heart failure (HF) patients is incompletely characterized. We aimed to assess the association of D-dimer levels on admission with adverse events at follow-up in patients hospitalized with HF across all ejection fraction (EF) phenotypes.

METHODS AND RESULTS

Consecutive patients hospitalized from December 2006 to December 2017 for HF with D-dimer and EF values available (n = 1795) were enrolled. Associations between D-dimer and all-cause death were examined at 1-year follow-up. Median age was 57 years, 73.4% were male, and the majority (72.1%) were in New York Heart Association Classes III-IV. EF was reduced in 53.3% (HFrEF), mildly reduced in 16.3% (HFmrEF), and preserved in 30.4% (HFpEF). Median (interquartile range) D-dimer on admission was 0.56 (0.27-1.295) μg/mL FEU (fibrinogen-equivalent unit) in the whole cohort, 0.64 (0.28-1.48) μg/mL FEU in HFrEF, 0.50 (0.27-1.03) μg/mL FEU in HFmrEF, and 0.495 (0.25-1.10) μg/mL FEU in HFpEF (P = 0.001). At 1-year follow-up, higher D-dimer (D-dimer ≥0.56 μg/mL FEU) independently predicted all-cause death in total cohort [hazard ratio (HR) 1.55; 95% confidence interval (CI), 1.15-2.1], in HFrEF (HR, 1.49; P = 0.039), and in HFpEF (HR, 2.06; P = 0.033). However, no relationship was found for HFrEF or HFmrEF when D-dimer was treated as quartiles. In sensitivity analysis, quantitatively similar but more pronounced association between D-dimer and all-cause death was observed in total cohort and HFpEF cohort.

CONCLUSIONS

In hospitalized HF patients, higher D-dimer concentration was a significant and independent predictor of 1-year all-cause mortality. Across all HF phenotypes, this effect was most evident in HFpEF patients.

Off-Label Use and Inappropriate Dosing of Direct Oral Anticoagulants in Cardiopulmonary Disease

Direct oral anticoagulants (DOACs) are increasingly used in clinical practice and have become essential in the management of atrial fibrillation and VTE. The enthusiasm for DOACs has fueled the off-label application of these agents in cardiopulmonary disease, and their use has often outpaced the evidence supporting their application. This article reviews the evidence and current off-label use of DOACs in various cardiopulmonary disease states.

Stroke and Thromboembolism in Patients with Heart Failure and Sinus Rhythm: A Matter of Risk Stratification?

Patients with heart failure (HF) in sinus rhythm (SR) experience an increased incidence of thromboembolic events including stroke. Among patients with HF, high-quality evidence supports the use of oral anticoagulation when atrial fibrillation (AF) is present, but the benefit of anticoagulation in SR in absence of other known indications for anticoagulation is unclear. In four randomized controlled trials (RCTs), warfarin did not improve a composite of clinical outcomes compared with aspirin or placebo in patients with HF with reduced ejection fraction (HFrEF) and SR. A recent RCT assessed the efficacy of the direct oral anticoagulant rivaroxaban versus placebo in patients with HFrEF (including mildly reduced ejection fraction), SR and coronary artery disease. While rivaroxaban had a neutral effect on the primary composite outcome of MI, stroke, or all-cause mortality, exploratory analyses revealed a significant reduction in strokes. It is thus possible that a subgroup of patients with HFrEF who are at high risk of stroke may benefit from anticoagulation. The challenge is to adequately identify this subgroup and to balance the potential benefit of anticoagulation with the risk of major bleeding. There is also an unmet need for evidence around anticoagulation in HF with preserved ejection fraction (HFpEF) and SR. This review explores the current evidence around anticoagulation in patients with HF and SR, identifies challenges regarding outcome definitions and patient selection, and offers suggestions for future research.

Anticoagulants for stroke prevention in heart failure with reduced ejection fraction

Impaired left-ventricular ejection-fraction (LV-EF) is a known risk factor for ischemic stroke and systemic embolism in patients with heart failure (HF) even in the absence of atrial fibrillation. While stroke risk is inversely correlated with LV-EF in HF patients with sinus rhythm, strategies using anticoagulation with Vitamin-K antagonists (VKA) were futile as the increase in major bleedings outweighed the potential benefit in stroke reduction. Non-Vitamin K oral anticoagulants (NOACs) proved to be an effective and in general safer approach for stroke prevention in patients with atrial fibrillation and may also have a favourable risk–benefit profile in HF patients. In HF patients with sinus rhythm, the COMPASS trial suggested a potential benefit for rivaroxaban, whereas the more dedicated COMMANDER-HF trial remained neutral on overall ischemic benefit owed to a higher mortality which was not influenced by anticoagulation. More recent data from subgroups in the COMMANDER-HF trial, however, suggest that there might be a benefit of rivaroxaban regarding stroke prevention under certain circumstances. In this article, we review the existing evidence for NOACs in HF patients with atrial fibrillation, elaborate the rationale for stroke prevention in HF patients with sinus rhythm, summarise the available data from anticoagulation trials in HF with sinus rhythm, and describe the patient who might eventually profit from an individualised strategy aiming to reduce stroke risk.

New-onset atrial fibrillation in patients with worsening heart failure and coronary artery disease: an analysis from the COMMANDER-HF trial

BACKGROUND

Atrial fibrillation (AF) in the presence of heart failure (HF) is associated with poor outcomes including a high-risk of stroke and other thromboembolic events. Identifying patients without AF who are at high-risk of developing this arrhythmia has important clinical implications.

AIMS

To develop a risk score to identify HF patients at high risk of developing AF.

METHODS

The COMMANDER-HF trial enrolled 5022 patients with HF and a LVEF ≤ 40%, history of coronary artery disease, and absence of AF at baseline (confirmed with an electrocardiogram). Patients were randomized to either rivaroxaban (2.5 mg bid) or placebo. New-onset AF was confirmed by the investigator at study visits.

RESULTS

241 (4.8%) patients developed AF during the follow-up (median 21 months). Older age (≥ 65 years), LVEF < 35%, history of PCI or CABG, White race, SBP < 110 mmHg, and higher BMI (≥ 25 kg/m²) were independently associated with risk of new-onset AF, whereas the use of DAPT was associated with a lower risk of new-onset AF. We then built a risk score from these variables (with good accuracy C-index = 0.71) and calibration across observed and predicted tertiles of risk. New-onset AF events rates increased steeply by increasing tertiles of the risk-score. Compared to tertile 1, the risk of new-onset AF was 2.5-fold higher in tertile 2, and 6.3-fold higher in tertile 3. Rivaroxaban had no effect in reducing new-onset AF. In time-updated models, new-onset AF was associated with a higher risk of subsequent all-cause death: HR (95%CI) 1.38 (1.11-1.73).

CONCLUSIONS

A well-calibrated risk-score identified patients at risk of new-onset AF in the COMMANDER-HF trial. Patients who developed AF had a higher risk of subsequent death. Risk of new-onset atrial fibrillation in patients with HFrEF and coronary artery disease.

Thromboembolism in Heart Failure Patients in Sinus Rhythm: Epidemiology, Pathophysiology, Clinical Trials, and Future Direction

Despite advances in medical and device therapy, patients with heart failure remain at high risk for morbidity and mortality. Experimental and clinical studies have shown an association between heart failure and a hypercoagulable state, and that patients with heart failure experience an increased incidence of stroke and other thromboembolic events, regardless of whether they are in atrial fibrillation. Although oral anticoagulation is recommended when atrial fibrillation is present, the benefits of this therapy in patients with heart failure in sinus rhythm are uncertain. Older randomized controlled trials comparing warfarin with antiplatelet therapy were, for the most part, underpowered and failed to show convincing benefits of warfarin therapy in this population. Several recent studies that assessed the effects of low-dose direct-acting oral anticoagulant therapy in patients with coronary artery disease in sinus rhythm either included or specifically targeted patients with heart failure. Post hoc analysis of their results showed that this treatment strategy was associated with improved outcomes in patients with acute coronary syndrome or stable coronary artery disease and also a significant reduction in thromboembolic events, including ischemic stroke. This review presents the rationale for anticoagulant therapy in patients with heart failure in sinus rhythm, discusses gaps in our knowledge base, offers suggestions for when anticoagulation might be considered, and identifies potential directions for future research.

Prognostic value of D-dimer/fibrinogen ratio in the adverse outcomes of patients hospitalized for heart failure

Aim: To evaluate the clinical value of plasma D-dimer/fibrinogen ratio (DFR) in patients hospitalized for heart failure (HF). Methods: Clinical data of 235 patients were retrospectively analyzed. Kaplan-Meier method and Cox regression analysis were used to identify significant prognosticators. Results: The Kaplan-Meier analysis showed that a higher DFR level was significantly associated with an increase in the end point outcomes, including HF readmission, thrombotic events and death (log-rank test: p < 0.001). The multivariate Cox regression analysis showed that the high tertile of DFR was significantly associated with the study end points (HR: 2.18; 95% CI: 1.31-3.62; p = 0.003), compared with the low tertile. Conclusion: DFR is a reliable prognostic indicator for patients hospitalized for HF.